My new bike needs a water bottle cage. There are tons of readily available, commercial options, many of them very affordable, but with some time on my hands in the middle of a global pandemic, why not print one?
Well, a water bottle cage does present a bit of a challenge for FDM printing. A functional cage should be light weight, fit standard mounting lugs, work with one hand, retain the water bottle while riding over “rough” terrain and have some level of aesthetic appeal.
Many of the available 3D models I found online had geometry similar to commercially available cages with overhang angles that are difficult to print without supports. Their designed print orientation is with the mounting plate on the printbed, which results in the water bottle retention loads torquing the cage structure across its layer lines. This can lead to the “wings” of the cage snapping off with sensitivity to any defects between any print layer.
The Raindrop Water Bottle Cage makes the most of the 3D printing process by considering the anisotropic material properties inherent to the FDM printing process. It is printed upright, with its base on the build plate, and without any required supports. The result is a light-weight cage, weighing in at around 40 grams in PETG, that is not stressed perpedicular to its layer lines as the bottle bounces around while biking over bumps and curbs.
I’ve been using this water bottle cage on my bike for about six months now, riding excusively on streets and paved or gravel bike paths (and admittedly not riding much at all in the winter months). It’ll be interesting to see how this holds up in the weather and across more bumpy terrain.